Ginkgo leaves come in very different shapes, all within one ancient species and sometimes even within one tree. Apparently, its leaf form is highly “plastic”. According to a quick internet search, factors that influence the shape of leaves are the indivdual’s genetics, environmental conditions, age of the tree, energy-conserving stragies of the tree and growth rate of the branch that it is on.

These are monoprints of leaves from the garden of one of my colleagues.